#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main()
{
   int num;
   FILE *fptr;

   // use appropriate location if you are using MacOS or Linux
   fptr = fopen("C:\\program.txt","w");

   if(fptr == NULL)
   {
      printf("Error!");   
      exit(1);             
   }

   sleep( 300 ) ; 
   fclose( fptr ) ; 
}